The National Association of Broadcasters (NAB) has unveiled a sweeping $697 million USD ad campaign to raise public awareness about the coming switchover to digital TV broadcasting.

Calling it "the largest volunteer effort in the history of television," NAB board chairman Jack Sander said all major broadcast networks and 95 independent broadcasting companies have teamed up on the program with the aim of reaching nearly every television viewer in the United States.

The campaign will consist of TV ads in English and Spanish, a 30-minute educational video and text "crawls" that run at the bottom of television screens during other programming. The ads seek to warn viewers that all U.S. broadcasters will stop transmitting analog signals on February 18, 2009.

After that date, the only TVs that will be able to receive "over the air" (OTA) programming via antenna will be television sets equipped with an internal or external digital tuner capable of picking up ATSC signals. Older analog TVs can be converted to receive ATSC programming via government-subsidized analog-to-digital converter boxes. Beginning next January, every U.S. household will be entitled to two $40 coupons to partly cover the cost of buying two converter boxes.

U.S. Commerce Secretary Carlos M. Gutierrez praised the NAB efforts. In a prepared statement, Gutierrez said the campaign "demonstrates that broadcasters nationwide will work to ensure that all households are aware of the... transition, so that no consumer will lose television reception because of a lack of information."

Consumer education efforts by industry, advocacy groups and government entities now total more than $900 million USD according to Gutierrez. "Industry and advocates are taking their responsibility seriously," he said, noting that the joint effort "far exceeds what the government alone could accomplish.”

The digital TV transition may still go largely unnoticed by most Americans, who have long since abandoned their rooftop antennas in favor of subscribing to cable and satellite TV programming services. Less than 20 percent of U.S. households currently rely on OTA antenna reception, according to a 2005 report by the Government Accountability Office.